If you're using a small amount of devices, sure. Routers lose speed on overhead, the more devices you place in the queue, the more it loses to each device. So what may seem fine to you may struggle with 10-15 active clients. Performance and quality wise, the Archer C8 falls short of the AC68, which is not a $500 router, it's way cheaper than that. The Archer C7 is terrible compared to the AC68.
If Router A has a total bandwidth capability of 1200 Mbps and Router B has a capability of 1000 Mbps, but router A has a far slower processor than router B, router B will be able to provide more end-client performance than the higher bandwidth router. From wired to wireless connection. And that's scratching the surface. Quality of components and how well the firmware was developed also control what you lose by the time you get the signal. If it were as simple as what you say, people would be able to use the same router for 6-7 years at a time.